While the Star Wars actress's official cause of death is listed as "cardiac arrest" in the document, the explanation is also marked as "deferred," which means that while it's been determined she indeed suffered a heart attack, it's unclear what set off the attack, Entertainment Tonightreports.

Meanwhile, Reynolds' certificate confirmed that the Hollywood icon passed away after having an intracerebral hemorrhage. Reynolds reportedly also suffered from hypertension and high blood pressure.

Fisher died on December 27, days after she went into cardiac arrest while on a flight from London and Los Angeles on December 22. The following day, Reynolds, who was Fisher's mother, died of a stroke.